Display device in which a sub-pixel has a plurality of apertures and electronic apparatus including the display device

ABSTRACT

A display device includes: plural sub-pixels included in a main pixel, emitting light of different colors respectively; at least three apertures arranged so as to be aligned along one direction in the sub-pixel; and an aperture defining portion defining aperture lengths so that an aperture length of an aperture other than apertures at both edge portions along the one direction is longer than an aperture length of apertures at both edge portions along the one direction in the at least three apertures.

RELATED APPLICATION DATA

This application is a continuation of U.S. patent application Ser. No.12/754,947, filed on Apr. 6, 2010, the entirety of which is incorporatedherein by reference to the extent permitted by law. The presentinvention claims priority to and contains subject matter related toJapanese Patent Application JP 2009-096609 filed in the Japanese PatentOffice on Apr. 13, 2009, the entire contents of which being incorporatedherein by reference.

BACKGROUND

The present invention relates to a display device and an electronicapparatus. More particularly, the invention relates to a display deviceand an electronic apparatus in which a main pixel is provided withplural sub-pixels displaying different colors, and the sub-pixel isdivided into plural apertures.

An organic EL (Electro-Luminescence) display device does not emit lightwhen there are foreign objects or the like in an organic EL lightemitting layer. This is a phenomenon in which a leakage path is formedbetween electrodes due to foreign objects mixed into electrodes of apixel and the entire pixel does not emit light. The entire pixels do notemit light also when foreign objects exist on a thin-film transistorsubstrate (TFT substrate) and power supply to the organic EL layer isshut off.

When the organic EL layer is formed by using a mask on the TFTsubstrate, it is difficult to completely exclude foreign objects. Sincea region in which a leakage path is actually generated is part of thepixel, when one pixel is divided into plural sub-pixels and remainingsub-pixels without leakage emit light normally, it is expected thatpixel defects are reduced.

For example, a structure in which one pixel is divided into pluralregions is disclosed in JP-A-2007-286081 (Patent Document 1). That is,one pixel is divided into plural TFTs or EL elements. Accordingly, evenwhen a leakage path is generated at any of divided regions, or even whenpower supply to the EL element is shut off, light emission (lighting) atother divided regions can be maintained. In this case, the lightemitting area of the EL element is reduced as compared with a normalpixel, however, a complete black dot defect can be avoided.

SUMMARY OF THE INVENTION

However, in a related-art display device in which the aperture area ofone main pixel is simply divided equally, when there is a defect at anaperture arranged at an edge portion, the distance from an aperture atwhich light emission is maintained to a light emitting region of anadjacent pixel becomes long. Accordingly, a black (non-light emitting)region becomes wide as compared with a case in which there is a defectat an aperture at the center portion, therefore, there arises a problemthat the region tends to be visible as a black dot.

In view of the above, in the case where a main pixel is divided intoplural aperture, it is desirable to avoid generation of difference invisibility as a non-light emitting region when a defect occurs at anyaperture.

According to a embodiment of the invention, there is provided a displaydevice including plural sub-pixels included in a main pixel, emittinglight of different colors respectively, at least three aperturesarranged so as to be aligned along one direction in the sub-pixel, andan aperture defining portion defining aperture lengths so that anaperture length of an aperture other than apertures at both edgeportions along the one direction is longer than an aperture length ofapertures at both edge portions along the one direction in the at leastthree apertures. Also according to the embodiment of the invention,there is provided an electronic apparatus including the display devicein a main casing thereof.

In the embodiment of the invention, even when a failure occurs at apixel corresponding to any one of the at least three apertures,distances between adjacent normal pixels can be approximately equal.

Specifically, in the embodiment of the invention, when a distancebetween the aperture other than apertures at both edge portions and anadjacent aperture is “a”, a distance between one of the apertures atboth edge portions and one of apertures at both edge portions in a mainpixel adjacent in one direction is “b”, an aperture length of one of theapertures at both edge portions along the one direction is “Le” and anaperture length of an aperture other than the apertures at both edgeportions along the one direction is “Ls”, a<b is satisfied, and further,Le+a+b=Ls+2a is satisfied.

According to the above, even when a failure occurs at a pixelcorresponding to any of at least three apertures, distances of normalpixels adjacent to the failure position can be approximately equal.

According to the embodiment of the invention, it is possible to providea display device in which, in the case where the main pixel is dividedinto plural apertures, the difference in visibility as a non-lightemitting region is not generated even when a failure occurs at anyaperture to thereby realizing high yield.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic plan view explaining an outline of a displaydevice according to an embodiment of the invention;

FIG. 2 is a schematic cross-sectional view of the display deviceaccording to the embodiment;

FIG. 3 is a plan view explaining a transistor structure of a pixelportion in a comparative example;

FIG. 4 a plan view explaining apertures of the pixel portion in thecomparative example;

FIG. 5 is a plan view explaining a transistor structure of a pixelportion in the embodiment;

FIG. 6 is a plan view explaining apertures of the pixel portion in theembodiment;

FIG. 7 is a circuit diagram explaining a circuit configuration of thepixel portion in the display device according to the embodiment;

FIG. 8 is a plan view explaining a specific example of apertures in thecomparative example;

FIG. 9 is a plan view explaining a specific example of apertures in theembodiment;

FIG. 10 is a plan view explaining a detailed specific example (No. 1) ofapertures in the display device according to the embodiment;

FIG. 11 is a plan view explaining a detailed specific example (No. 2) ofapertures in the display device according to the embodiment;

FIG. 12 is a perspective view showing a television set to which theembodiment is applied;

FIG. 13A and FIG. 13B are perspective views showing a digital camera towhich the embodiment is applied;

FIG. 14 is a perspective view showing a notebook personal computer towhich the embodiment is applied;

FIG. 15 is a perspective view showing an appearance of a video camera towhich the embodiment is applied; and

FIG. 16A to FIG. 16G are views showing a portable terminal device, forexample, a cellular phone device to which the embodiment is applied.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Herein after, a best mode for carrying out the invention (referred to asan “embodiment” in the following description) will be explained. Theexplanation will be made in the following order.

1. Outline of a display device (Whole configuration, Cross-sectionalstructure)

2. Configuration of a pixel portion (Comparative example, Basicconfiguration of the embodiment, Circuit configuration)

3. Specific example (Comparative example, Present embodiment, Specificexamples: No. 1, No. 2)

4. Application example

1. Outline of a Display Device

[Whole Configuration]

FIG. 1 is a schematic plan view explaining an outline of the wholeconfiguration of a display device according to an embodiment of theinvention. That is, a display device 1 includes a display region 10provided at approximately the center of a support substrate such as aglass substrate, power supply portions 20 arranged at the periphery ofthe display region 10, signal line input portions 21, a scanning signalinput portions 24 and power supply control signal input portions 25.

In the display region 10, plural pixel portions 30 are arrangedvertically and horizontally in a matrix state. In the display devicedisplaying color images, an assortment of pixel portions 30corresponding to, for example, R (red), G (green) and B (blue)constitutes a display pixel.

Each pixel portion 30 includes a drive portion 31 a having a drivetransistor. The drive transistor of the drive portion 31 a is made of athin-film transistor (TFT) formed on a substrate, which drives a drivetarget provided in the pixel portion 30 by voltage application.

When the drive target in the pixel portion 30 is the organic EL (ElectroLuminescence) layer, an electric field given to the organic EL layercorresponding to respective colors is controlled by the drivetransistor. When the drive target in the pixel portion 30 is the liquidcrystal layer, the electric field given to the liquid crystal iscontrolled by the drive transistor.

A power supply control line 22 and a scanning line 23 are connected tothe drive transistor, and the drive transistors in the display region 10are sequentially driven by the scanning signal input portions 24 tothereby display images.

That is, power supply voltage is supplied to a horizontal pixel rowselected by the scanning line 23 from the power supply control line 22,and display of the pixel is performed in accordance with a pixel signalinputted from the signal line input portion 21 in the vertical pixelcolumn direction through a signal line 26. The selection of thehorizontal pixel row by the scanning lines 23 and the input of pixelsignals from the signal lines 26 are synchronized to drive the displayregion 10, as a result, images are displayed.

In order to manufacture the drive substrate 1, respective layers such asa semiconductor layer and an insulating film layer are formed on thesupport substrate by a deposition process, for example, a CVD (ChemicalVapor Deposition) and the like, and drive elements are formed and wiringis patterned by an impurity implantation process, a photolithographyprocess and so on.

[Cross-Sectional Structure]

FIG. 2 is a schematic cross-sectional view explaining a configurationexample of a drive transistor in a pixel portion. That is, a gateelectrode Trg which is a first metal layer is formed within a glasssubstrate 40 and a semiconductor layer 42 is formed thereon through agate insulating film 41.

The semiconductor layer 42 is formed by amorphous silicon being annealedand crystallized by irradiating laser light. Over the semiconductorlayer 42, an n+ layer is formed right and left of an etching stopper 43.A source electrode Trs and a drain electrode Trd which are second metallayers are formed through the n+ layer.

A passivation film 44 is formed on the drive transistor 31, and an anodeelectrode 51 is formed through an insulating planarization film 45 to beformed thereon.

Furthermore, an insulating film for defining apertures 46 which definesapertures is formed on the anode electrode 51, and an organic EL layeris formed within the aperture on the anode electrode 51. Additionally, acathode electrode 52 is formed on the organic EL layer over the wholesurface.

2. Configuration of a Pixel Portion

Next, a configuration of a pixel portion in the display device accordingto the embodiment will be explained. In order to make the configurationof the pixel portion of the display device in the embodiment easilyunderstandable, explanation will be made with a comparative example.

Comparative Example

FIG. 3 is a plan view explaining the transistor structure of a pixelportion in a comparative example. In FIG. 3, a transistor structure inone main pixel corresponding to any one color of R (red), G (green) andB (blue) is shown. In the pixel portion, three drive transistors Tr-d1to Tr-d3 are provided in one main pixel, and three write transistorsTr-w1 to Tr-w3 and three storage capacitors Cs1 to Cs3 are provided soas to correspond to these drive transistors.

In the main pixel, gate electrodes of the write transistors Tr-w1 toTr-w3 are connected to the scanning line 23 in common. Also, drainelectrodes of the write transistors Tr-w1 to Tr-w3 are connected to thesignal line 26 in common. Additionally, drain electrodes of the drivetransistors Tr-d1 to Tr-d3 are connected to the power supply controlline 22 in common. Accordingly, three write transistors Tr-w1 to Tr-w3and three drive transistors Tr-d1 to Tr-d3 operate at the same time inthe main pixel.

FIG. 4 is a plan view explaining apertures of the pixel portion in thecomparative example. The plan view shows a layout of anode electrodes 51and apertures corresponding to the transistor structure of one mainpixel shown in FIG. 3. The anode electrodes 51 are connected to sourceelectrodes of respective drive transistors Tr-d1 to Tr-d3 shown in FIG.3 through contacts. Since there are three drive transistors Tr-d1 toTr-d3 in the example shown in FIG. 3, three anode electrodes 51 areprovided so as to correspond to these transistors.

A first aperture S1, a second aperture S2 and a third aperture S3 areprovided at regions inside the three anode electrodes 51. The aperturesize of the first aperture S1, the second aperture S2 and the thirdaperture S3 is determined by the insulating film for defining apertures46. Though the insulating film for defining apertures 46 is used as acomponent for determining the aperture size, a shielding film to beprovided at an upper layer can be used as an aperture defining portion.Emitted light is irradiated from the respective apertures S1 to S3.

In the comparative example, when the aperture size of the first apertureS1 is W1, the aperture size of the second aperture S2 is W2 and theaperture size of the third aperture S3 is W3, W1=W2=W3, that is, therespective apertures are provided with equal size.

Basic Configuration of the Embodiment

FIG. 5 is a plan view explaining a transistor structure of a pixelportion in the embodiment. In FIG. 5, the transistor structure of onemain pixel corresponding to any one color of R (red), G (green) and B(blue) is shown. In the pixel portion, three drive transistors Tr-d1 toTr-d3 are provided in one main pixel, and three write transistors Tr-w1to Tr-w3 and three storage capacitors Cs1 to Cs3 are provided so as tocorrespond to these drive transistors.

In the main pixel, gate electrodes of the write transistors Tr-w1 toTr-w3 are connected to the scanning line 23 in common. Also, drainelectrodes of the write transistors Tr-w1 to Tr-w3 are connected to thesignal line 26 in common. Additionally, drain electrodes of the drivetransistors Tr-d1 to Tr-d3 are connected to the power supply controlline 22 in common. Accordingly, three write transistors Tr-w1 to Tr-w3and three drive transistors Tr-d1 to Tr-d3 operate at the same time inthe main pixel.

FIG. 6 is a plan view explaining apertures of the pixel portion in theembodiment. The plan view shows a layout of anode electrodes 51 andapertures corresponding to the transistor structure of one main pixelshown in FIG. 5. The anode electrodes 51 are connected to sourceelectrodes of respective drive transistors Tr-d1 to Tr-d3 shown in FIG.5 through contacts. Since there are three drive transistors Tr-d1 toTr-d3 in the example shown in FIG. 5, three anode electrodes 51 areprovided so as to correspond to these transistors.

The first aperture S1, the second aperture S2 and the third aperture S3are provided at regions inside the three anode electrodes 51. Theaperture size of the first aperture S1, the second aperture S2 and thethird aperture S3 is determined by the insulating film for definingapertures 46. Though the insulating film for defining apertures 46 isused as the component for determining the aperture size, a shieldingfilm to be provided at an upper layer can be used as an aperturedefining portion. Emitted light is irradiated from the respectiveapertures S1 to S3.

In the embodiment, when the aperture size of the first aperture S1, theaperture size of the second aperture S2 is W2 and the aperture size ofthe third aperture S2 is W3, W2 is larger than W1 and W3. That is, W1,W2 and W3 are formed to be equal in the comparative example explainedabove, however, the aperture size W2 provided at a position other thanboth edge portions is formed to be larger than the aperture sizes W1, W3arranged at both edge portions in the embodiment.

[Circuit Configuration]

FIG. 7 is a circuit diagram explaining a circuit configuration of thepixel portion in the display device according to the embodiment. In theembodiment, three apertures are provided at the main pixel and threewrite transistors Tr-w1 to Tr-w3 and three drive transistors Tr-d1 toTr-d3 and three storage capacitors Cs1 to Cs 3 are provided so as tocorrespond to the respective apertures.

Gate electrodes of respective write transistors Tr-w1 to Tr-w3 areconnected to a not-shown scanning line, drain electrodes of respectivewrite transistors Tr-w1 to Tr-w3 are connected to the signal line 26.

Additionally, source electrodes of respective write transistors Tr-w1 toTr-w3 are connected to gate electrodes of corresponding drivetransistors Tr-d1 to Tr-d3 respectively. Drain electrodes of respectivedrive transistors Tr-d1 to Tr-d3 are connected to the power supplycontrol line in common, to which power supply voltage is supplied.Source electrodes of respective drive transistors Tr-d1 to Tr-d3 areconnected to anode electrodes of the organic EL light emitting layer.Cathode electrodes of the organic EL light emitting layer are groundedin common. The respective storage capacitors Cs1 to Cs3 are connectedbetween gates and sources of corresponding drive transistors Tr-d1 toTr-d3.

In the above circuit configuration, when a signal is inputted to thescanning line, three write transistors Tr-w1 to Tr-w3 are turned on, andthe signal is stored in respective storage capacitors Cs1 to Cs3 fromthe signal line 26. The drive transistors Tr-d1 to Tr-d3 are operated inaccordance with the signal, and voltage corresponding to the signal isapplied to the anode electrodes of the organic EL light emitting layer.The organic EL light emitting layer emits light by the voltage.

3. Specific Example

Next, a specific example of apertures in the pixel portion will beexplained. The explanation of the specific example will be made with acomparative example in order to make the embodiment easilyunderstandable.

Comparative Example

FIG. 8 is a plan view explaining a specific example of apertures in thecomparative example. In the drawing, apertures of two main pixels P-1,P-2 which are vertically adjacent are shown. Since the apertures of twomain pixels P-1, P-2 are the same, a layout of the apertures will beexplained by using the main pixel P-1 here.

In the main pixel P-1, three sub-pixels p1, p2 and p3 are provided. Eachof sub-pixels p1, p2 and p3 emits light corresponding to one colorrespectively. For example, the sub-pixel p1 emits light corresponding toR (red), the sub-pixel p2 emits light corresponding to G (green) and thesub-pixel p3 emits light corresponding to B (blue).

Respective sub-pixels p1, p2 and p3 are laid out so that three aperturesS1, S2 and S3 are aligned in one direction (vertical direction in thedrawing) according to corresponding colors. The aperture sizes ofrespective apertures S1, S2 and S3 are defined by an aperture definingportion K (for example, an insulating film for defining apertures or ashielding film). In the comparative example, the apertures are providedso that the aperture sizes of respective apertures S1, S2 and S3 areequal.

The three apertures S1, S2 and S3 provided at respective sub-pixels p1,p2 and p3 emit light at the same time so as to correspond to respectivecolors. That is, when light of R (red) in the main pixel P-1 is emitted,light is emitted from three apertures S1 to S3 of the sub-pixel p1corresponding to R (red) at the same time. Similarly, when light of G(green) in the main pixel P-1 is emitted, light is emitted from threeapertures S1 to S3 of the sub-pixel p2 corresponding to G (green) at thesame time. Also similarly, when light of B (blue) in the main pixel P-1is emitted, light is emitted from three apertures S1 to S3 of thesub-pixel p3 corresponding to B (blue) at the same time.

Here, a case in which a light emission failure occurs at any one ofthree apertures S1, S2 and S3 in each of the sub-pixels p1, p2 and p3will be explained. The light emission failure occurs due to a failure ofa transistor corresponding to each of apertures S1, S2 and S3 or afailure between electrodes in the organic EL light emitting layer. Inthe following explanation, the light emission failure caused by thefailure of the transistor corresponding to the aperture or the failureof the organic EL light emitting layer will be just expressed as a lightemission failure at an aperture.

For example, assume that the aperture S3 arranged at the lower edgeportion of the sub-pixel p1 corresponding to R (red) shown in FIG. 8 hasa light emission failure. Since the aperture S3 does not emit light inthis case, a distance between apertures which normally emit light willbe a distance D between the aperture S2 adjacent to the aperture S3having the light emission failure in the upward direction and theaperture S1 of the sub-pixel p1 in the main pixel P-2 adjacent in thedownward direction. In this case, the case in which the light emissionfailure occurs at the aperture S3 of the sub-pixel p1 corresponding to R(red) is cited as an example, however, it is also the same in cases inwhich the failure occurs at apertures S3 of the sub-pixels p2, p3corresponding to G (green) and B (blue).

Present Embodiment

FIG. 9 is a plan view explaining a specific example of apertures in theembodiment. In the drawing, apertures of two main pixels P-1, P-2 whichare vertically adjacent are shown. Since the apertures of two mainpixels P-1, P-2 are the same, a layout of the apertures will beexplained by using the main pixel P-1 here.

In the main pixel P-1, three sub-pixels p1, p2 and p3 are provided. Eachof sub-pixels p1, p2 and p3 emits light corresponding to one colorrespectively. For example, the sub-pixel p1 emits light corresponding toR (red), the sub-pixel p2 emits light corresponding to G (green) and thesub-pixel p3 emits light corresponding to B (blue).

Respective sub-pixels p1, p2 and p3 are laid out so that three aperturesS1, S2 and S3 are aligned in one direction (vertical direction in thedrawing) according to corresponding colors. The aperture sizes ofrespective apertures S1, S2 and S3 are defined by the aperture definingportion K (for example, an insulating film for defining apertures or ashielding film). In the embodiment, the apertures are provided so thatthe aperture size of the aperture S2 other than apertures at both edgeportions is larger than the aperture size of the apertures S1, S3 atboth edge portions in the three apertures S1, S2 and S3.

The three apertures S1, S2 and S3 provided at respective sub-pixels p1,p2 and p3 emit light at the same time so as to correspond to respectivecolors. That is, when light of R (red) in the main pixel P-1 is emitted,light is emitted from three apertures S1 to S3 of the sub-pixel p1corresponding to R (red) at the same time. Similarly, when light of G(green) in the main pixel P-1 is emitted, light is emitted from threeapertures S1 to S3 of the sub-pixel p2 corresponding to G (green) at thesame time. Also similarly, when light of B (blue) in the main pixel P-1is emitted, light is emitted from three apertures S1 to S3 of thesub-pixel p3 corresponding to B (blue) at the same time.

Here, a case in which a light emission failure occurs at any one ofthree apertures S1, S2 and S3 in each of the sub-pixels p1, p2 and p3will be explained. The light emission failure occurs due to a failure ofa transistor corresponding to each of apertures S1, S2 and S3, a failurebetween electrodes in the organic EL light emitting layer or the like.

For example, assume that the aperture S3 arranged at the lower edgeportion of the sub-pixel p1 corresponding to R (red) shown in FIG. 9 hasa light emission failure. Since the aperture S3 does not emit light inthis case, a distance between apertures which normally emit light willbe a distance D′ between the aperture S2 adjacent to the aperture S3having the light emission failure in the upward direction and theaperture S1 of the sub-pixel p1 in the main pixel P-2 adjacent in thedownward direction. In this case, the case in which the light emissionfailure has occurred in the aperture S3 of the sub-pixel p1corresponding to R (red) is cited as an example, however, it is also thesame in cases in which the failure occurs at apertures S3 of thesub-pixels p2 and p3 corresponding to G (green) and B (blue).

When comparing the embodiment with the comparative example, in the casewhere the light emission failure occurs at the same aperture S3 of thesub-pixel p1 corresponding to R (red), the distance of aperturesnormally emit light is D in the comparative example, whereas it is D′ inthe embodiment. The distance D′ in the embodiment is shorter than thedistance D in the comparative example. This is because the aperturesizes of the apertures S1, S2 and S3 included in respective sub-pixelsp1, p2 and p3 are not equal and the aperture size of the aperture S2other than apertures at edge portions is larger than those of theapertures S1, S3 at edge portions. Accordingly, in the embodiment, anon-light emitting region in the case where the light emission failureoccurs at the aperture S3, namely, the distance D′ will be shorter thanthe distance D in the comparative example, as a result, it is hardlyvisible as a non-light emitting region.

Next, specific examples of apertures in the display device according tothe embodiment will be explained.

Detailed Specific Example of the Embodiment: No. 1

FIG. 10 is a plan view explaining a detailed specific example (No. 1) ofapertures in the display device according to the embodiment. In thedrawing, apertures in two main pixels P-1, P-2 adjacent in the verticaldirection are shown. Concerning the layout of apertures shown in FIG.10, three apertures S1, S2 and S3 are aligned in one direction (verticaldirection in the drawing) in each of sub-pixels p1, p2 and p3respectively formed in the main pixels P-1, P-2 in the same manner asthe layout of apertures shown in FIG. 9. The sizes of respectiveapertures S1, S2 and S3 are defined by the aperture defining portion K.

Since the same layout of apertures as the specific example shown in FIG.9 is applied in the detailed specific example shown in FIG. 10, detailedexplanation of the main pixels P-1, P-2, the sub-pixels p1, p2 and p3and the apertures S1, S2 and S3 is omitted. Therefore, the sizeconfiguration about the respective apertures S1, S2 and S3 as well asdistances therebetween will be explained below in detail. Also, thelayout of apertures is the same in respective sub-pixel p1, p2 and p3,therefore, explanation will be made by using the sub-pixel p1.

As sizes used in explanation of the example shown in FIG. 10, lengthsalong the vertical direction in the drawing (direction of alignment ofapertures S1 to S3) are used. As the lengths along this direction, anaperture length of the aperture S1 is denoted as L1, an aperture lengthof the aperture S2 is denoted as L2 and an aperture length of theaperture S3 is denoted as L3. A distance between the aperture S1 and theaperture S2 as well as a distance between the aperture S2 and theaperture S3 are denoted as “a”. Additionally, a distance between theaperture S3 and the aperture S1 of the sub-pixel in the main pixel P-2adjacent in the downward direction is denoted as “b”. A length of themain pixel P-1 is denoted as L.

In the example shown in FIG. 10, the aperture size L1 of the aperture S1arranged at the upper edge portion of the sub-pixel p1 is equal to theaperture size L3 of the aperture S3 arranged at the lower edge portion.L1=L3

The aperture size L2 of the aperture S2 arranged at the center of thesub-pixel p1 is larger than the aperture sizes L1, L3 of the aperturesS1, S3 at the edge portions.L2>L1,L2>L3

The distance “a” between the aperture S1 and the aperture S2 and thedistance “a” between the aperture S2 and the aperture S3 in thesub-pixel p1 are smaller than the distance “b” between the aperture S3at the lower edge portion of the sub-pixel p1 in the main pixel P-1 andthe aperture S1 at the upper edge portion of the sub-pixel p1 in themain pixel P-2 which is adjacent to the main pixel P-1 in the verticaldirection.a<b

Moreover, a sum of the aperture size L3 of the aperture S3, the distance“a” above L3 and the distance “b” below L3 is equal to a sum of theaperture size L2 of the aperture S2, the distance “a” above L2 and thedistance “a” below L2.L3+a+b=L2+2a

Furthermore, aperture lengths of the three apertures S1, S2 and S3 inthe sub-pixel p1 along the horizontal direction in the drawing areequal. The length L of the main pixel P-1 is equal to L1+L2+L3+2a+b.

According to the above relationship, when the light emission failureoccurs in any of the three apertures S1, S2 and S3, distances betweenadjacent apertures which normally emit light can be approximately equalin the embodiment.

For example, when the light emission failure occurs at the aperture S3arranged at the lower edge portion of the sub-pixel p1, a length of aregion in which light of color corresponding to the sub-pixel p1 (red)is reduced will be the length obtained by adding the aperture size L3 ofthe aperture S3 to the distances “a”, “b” which are above and below theaperture S3. That is, when the light emission failure occurs at theaperture S3, the distance from the lower edge of the aperture S2adjacent in the upward direction to the upper edge of the aperture S1positioned at the upper edge portion of the sub-pixel p1 in the mainpixel P-2 adjacent in the downward direction will be the region in whichlight emission failure occurs. The light emission failure region isexpressed as L3+a+b.

When the light emission failure occurs at the aperture S2 arranged atthe center of the sub-pixel p1, a length of a region in which light ofcolor corresponding to the sub-pixel p1 (red) is reduced will be thelength obtained by adding the aperture size L2 of the aperture S2 torespective distances “a” which are above and below the aperture S2. Thatis, when the light emission failure occurs at the aperture S2, thedistance from the lower edge of the aperture S1 adjacent in the upwarddirection to the upper edge of the aperture S3 adjacent in the downwarddirection will be the region in which light emission failure occurs. Thelight emission failure region is expressed as L2+2a.

In the embodiment, the light emission failure region L3+a+b in the casewhere the aperture S3 has the light emission failure is equal to thelight emission region L2+2a in the case in which the aperture S2 has thelight emission failure.

According to this, when the light emission failure occurs at any of thethree apertures S1, S2 and S3 provided in the sub-pixel p1, distancesbetween apertures which normally emit light adjacent above and below theaperture having the failure can be equal. That is, when the lightemission failure occurs at any aperture, the light emission failureregions will be equal, therefore, the difference in visibility as anon-light emitting region is not generated according to the position ofthe aperture.

The example of L3+a+b=L2+2a has been explained as the above, however,L3+a+b≦L2+2a is also preferable. This relational expression includesL3+a+b<L2+2a, however, in that case, even when the light emissionfailure occurs at the aperture S2 arranged at the center of thesub-pixel p1, the difference in visibility as the non-light emittingregion can be interpolated by increasing light emitting luminance of theapertures S1, S3 which normally emit light.

Detailed Specific Example of the Embodiment: No. 2

FIG. 11 is a plan view explaining a detailed specific example (No. 2) ofapertures in the display device according to the embodiment. In thedrawing, apertures in two main pixels P-1, P-2 adjacent in the verticaldirection are shown. Concerning the layout of apertures shown in FIG.11, four apertures S1, S2, S3 and S4 are aligned in one direction(vertical direction in the drawing) in each of sub-pixels p1, p2 and p3respectively formed in the main pixels P-1, P-2. The sizes of respectiveapertures S1 to S4 are defined by the aperture defining portion K.

In the following description, the size configuration about therespective apertures S1, S2, S3 and S4 as well as distances therebetweenwill be explained in detail. Also, the layout of apertures is the samein respective sub-pixel p1, p2 and p3, therefore, explanation will bemade by using the sub-pixel p1.

As sizes used in explanation of the example shown in FIG. 11, lengthsalong the vertical direction in the drawing (direction of alignment ofapertures S1 to S4) are used. As the lengths along this direction, anaperture length of the aperture S1 is denoted as L1, an aperture lengthof the aperture S2 is denoted as L2, an aperture length of the apertureS3 is denoted as L3 and an aperture length of the aperture S4 is denotedas L4. A distance between the aperture S1 and the aperture S2, adistance between the aperture S2 and the aperture S3 and a distancebetween the aperture S3 and the aperture S4 are denoted as “a”.Additionally, a distance between the aperture S4 and the aperture S1 ofthe sub-pixel in the main pixel P-2 adjacent in the downward directionis denoted as “b”. A length of the main pixel P-1 is denoted as L.

In the example shown in FIG. 11, the aperture size L1 of the aperture S1arranged at the upper edge portion of the sub-pixel p1 is equal to theaperture size L4 of the aperture S4 arranged at the lower edge portion.L1=L4

The aperture size L2 of the aperture S2 and the aperture size L3 of theaperture S3 arranged at positions other than both edge portions in thesub pixel p1 are equal.L2=L3

The aperture sizes L2, L3 of the apertures S2, S3 arranged at positionsother than both edge portions of the sub pixel p1 are larger than theaperture sizes L1, L4 of the apertures S1, S4 at edge portions.L2=L3>L1=L4

The distance “a” between respective apertures S1 to S4 in the sub-pixelp1 are smaller than the distance “b” between the aperture S4 at thelower edge portion of the sub-pixel p1 in the main pixel P-1 and theaperture S1 at the upper edge portion of the sub-pixel p1 in the mainpixel P-2 which is adjacent to the main pixel P-1 in the verticaldirection.a<b

Moreover, a sum of the aperture size L4 of the aperture S4, the distance“a” above L4 and the distance “b” below L4 is equal to a sum of theaperture size L2 or the aperture size L3 of the aperture S2 or theaperture S3, the distance “a” above L2 or L3 and the distance “a” belowL2 or L3.L4+a+b=L2+2aL4+a+b=L3+2a

Furthermore, aperture lengths of the four apertures S1, S2, S3 and S4 inthe sub-pixel p1 along the horizontal direction in the drawing areequal. The length L of the main pixel P-1 is equal to L1+L2+L3+L4+3a+b.

According to the above relationship, when the light emission failureoccurs in any of the four apertures S1, S2, S3 and S4, distances betweenadjacent apertures which normally emit light can be approximately equalin the embodiment.

For example, when the light emission failure occurs at the aperture S4arranged at the lower edge portion of the sub-pixel p1, a length of aregion in which light of color corresponding to the sub-pixel p1 (red)is reduced will be the length obtained by adding the aperture size L4 ofthe aperture S4 to the distances “a”, “b” which are above and below theaperture S4. That is, when the light emission failure occurs at theaperture S4, the distance from the lower edge of the aperture S3adjacent in the upward direction to the upper edge of the aperture S1positioned at the upper edge portion of the sub-pixel p1 in the mainpixel P-2 adjacent in the downward direction will be the region in whichlight emission failure occurs. The light emission failure region isexpressed as L4+a+b.

When the light emission failure occurs at the aperture S2 or theaperture S3 arranged at the center of the sub-pixel p1, a length of aregion in which light of color corresponding to the sub-pixel p1 (red)is reduced will be the length obtained by adding the aperture size L2 ofthe aperture S2 or the aperture size L3 of the aperture S3 to respectivedistances “a” which are above and below the aperture S2 or the apertureS3. That is, when the light emission failure occurs at the aperture S2,the distance from the lower edge of the aperture S1 adjacent in theupward direction to the upper edge of the aperture S3 adjacent in thedownward direction will be the region in which light emission failureoccurs. The light emission failure region is expressed as L2+2a. Also,when the light emission failure occurs at the aperture S3, the distancefrom the lower edge of the aperture S2 adjacent in the upward directionto the upper edge of the aperture S4 adjacent in the downward directionwill be the region in which light emission failure occurs. The lightemission failure region is expressed as L3+2a.

In the embodiment, the light emission failure region L4+a+b in the casewhere the aperture S4 has the light emission failure is equal to thelight emission failure region L2+2a or L3+2a in the case where theaperture S2 or the aperture S3 has the light emission failure.

In the case where four apertures S1 to S4 are provided at the sub-pixelp1 as described above, the same effects as the case of three aperturescan be obtained. That is, when the light emission failure occurs at anyof the four apertures S1, S2, S3 and S4, distances between adjacentapertures which normally emit light can be approximately equal.Therefore, when the light emission failure occurs at any aperture, thelight emission failure regions will be equal, therefore, the differencein visibility as a non-light emitting region is not generated accordingto the position of the aperture.

The examples of L4+a+b=L2+2a, L4+a+b=L3+2a have been explained as theabove, however, L4+a+b≦L2+2a, L4+a+b≦L3+2a are also preferable. Thisrelational expressions include L4+a+b<L2+2a, L4+a+b<L3+2a, however, inthe same manner as the above, even when the light emission failureoccurs at the aperture S2 or S3 arranged at the center of the sub-pixelp1, the difference in visibility of the non-light emitting region can beinterpolated by increasing light emitting luminance of the apertureswhich normally emit light.

In addition to the case of three apertures and the case of fourapertures as described above, the same concept can be applied also tocases of five or more apertures, whereby the same effects can beobtained.

4. Application Example

The display device according to the embodiment described above can beapplied to various electronic apparatuses by being provided in maincasings thereof. As examples, the display device can be applied tovarious electronic apparatuses shown in FIG. 12 to FIG. 16G. Forexample, the invention can be applied to display devices of electronicapparatuses in various fields in which a video signal inputted to theelectronic apparatus or a video signal generated in the electronicapparatus is displayed as images or video, such as a digital camera, anotebook personal computer, portable terminal devices such as a cellularphone and a video camera.

As described above, the display device according to the embodiment isused as display devices for electronic apparatuses in various fields,thereby improving image quality of display images, therefore, there isan advantage that good quality images can be displayed in variouselectronic apparatuses.

The display device according to the embodiment also includes amodule-shaped device having a sealed structure. For example, a displaymodule formed by a pixel array portion 102 being bonded to an oppositeportion such as a transparent glass is appropriate. It is alsopreferable that color filters, a protection film, a shielding film andso on are provided on the transparent opposite portion. The displaymodule may be provided with a circuit portion or a FPC (flexible printcircuit) for inputting and outputting a signal and the like from theoutside to the pixel array portion.

Specific examples of electronic apparatuses to which the display deviceaccording to the embodiment is applied will be explained below.

FIG. 12 is a perspective view showing an appearance of a television setto which the embodiment is applied. The television set according to theapplication example includes a video display screen portion 107 having afront panel 108, a filter glass 109 and the like, which is manufacturedby using the display device according to the embodiment as the videodisplay screen portion 107.

FIG. 13A and FIG. 13B are perspective views showing an appearance of adigital camera to which the embodiment is applied. FIG. 13A is aperspective view seen from the front and FIG. 13B is a perspective viewseen from the back. The digital camera according to the embodimentincludes a light emitting portion 111 for flash, a display portion 112,a menu switch 113, a shutter button 114 and so on, which is manufacturedby using the display device according to the embodiment as the displayportion 112.

FIG. 14 is a perspective view showing an appearance of a notebookpersonal computer to which the embodiment is applied. The notebookpersonal computer according to the application example includes a body121, a keyboard 122 operated when inputting characters and the like anda display portion 123 displaying images and so on, which is manufacturedby using the display device according to the embodiment as the displayportion 123.

FIG. 15 is a perspective view showing an appearance of a video camera towhich the embodiment is applied. The video camera according to theapplication example includes a body 131, a lens 132 for imaging objectsat a side surface facing the front and a start/stop switch 133 used atthe time of imaging and a display portion 134 and the like, which ismanufactured by using the display device according to the embodiment asthe display portion 134.

FIG. 16A to FIG. 16G are exterior views showing a portable terminaldevice, for example, a cellular phone device to which the embodiment isapplied. FIG. 16A is a front view in an opened state, FIG. 16B is a sideview thereof, FIG. 16C is a front view in an closed state, FIG. 16D is aleft-side view, FIG. 16E is a right-side view, FIG. 16F is an uppersurface view and FIG. 16G is a lower surface view. The cellular phonedevice according to the embodiment includes an upper casing 141, a lowercasing 142, a connecting portion (a hinge portion in this case) 143, adisplay 144, a sub-display 145, a picture light 146, a camera 147 and soon, which is manufactured by using the display device according to theembodiment as the display 144 or the sub-display 145.

It should be understood by those skilled in the art that variousmodifications, combinations, sub-combinations and alterations may occurdepending on design requirements and other factors insofar as they arewithin the scope of the appended claims or the equivalents thereof.

What is claimed is:
 1. A display device comprising: a main pixelincluding a plurality of sub-pixels, the plurality of sub-pixelsconfigured to emit light of different colors respectively, each of theplurality of sub-pixels including at least four apertures that arealigned along one direction, two of the at least four apertures being atrespective opposite ends of the main pixel along the one direction; andan aperture defining portion defining aperture lengths of the at leastfour apertures so that aperture lengths, along the one direction, ofapertures other than the two apertures at the opposite ends of the mainpixel are (i) longer than aperture lengths, along the one direction, ofthe two apertures at the opposite ends of the main pixel and (ii) equalto each other.
 2. The display device according to claim 1, wherein, whena distance between an aperture of the apertures other than the twoapertures at the opposite ends of the main pixel and an adjacentaperture is “a”, and a distance between one of the two apertures at theopposite ends of the main pixel and another aperture at an end ofanother main pixel adjacent to the main pixel in the one direction is“b”, a<b is satisfied.
 3. The display device according to claim 1,wherein aperture lengths of the at least four apertures in the sub-pixelalong a direction orthogonal to the one direction are equal.
 4. Thedisplay device according to claim 1, wherein light can be emittedthrough the at least four apertures.
 5. The display device according toclaim 1, wherein the main pixel includes an organic electro luminescence(EL) layer for light emission.
 6. An electronic apparatus comprising adisplay device in a main casing, wherein the display device includes:(a) a main pixel including a plurality of sub-pixels, the plurality ofsub-pixels configured to emit light of different colors respectively,each of the plurality of sub-pixels including at least four aperturesthat are aligned along one direction, two of the at least four aperturesbeing at respective opposite ends of the main pixel along the onedirection; and (b) an aperture defining portion defining aperturelengths of the at least four apertures so that aperture lengths, alongthe one direction, of apertures other than the two apertures at theopposite ends of the main pixel are (i) longer than aperture lengths,along the one direction, of the two apertures at the opposite ends ofthe main pixel and (ii) equal to each other.
 7. The electronic apparatusaccording to claim 6, wherein light can be emitted through the at leastfour apertures.
 8. The electronic apparatus according to claim 6,wherein the main pixel includes an organic electro luminescence (EL)layer for light emission.